Objectives: The prevalence of pervasive developmental disorders (PDDs) has increased. There has been speculation regarding a role of thimerosal-containing vaccines (TCVs) in this trend. Our objectives were to determine prevalence rates of PDDs among school-aged children, and to evaluate the impact of discontinuation of thimerosal use in 1996 in routine childhood vaccines on PDD rates.
Method: Children (n = 23 635) attending kindergarten to Grade 11 were surveyed in 71 schools from the English Montreal School Board. For children with PDD, information was obtained about their diagnostic subtype, age, sex, grade, and school. Prevalence rates were calculated for the entire school population and for each grade. Prevalence rates were also compared for children born before or after 1996.
Results: Students (n = 187; male to female ratio: 5.4:1) with PDD were identified, corresponding to a prevalence of 79.1/10 000 (95% CI 67.8 to 90.4/10 000). The prevalence was 25.4, 43.6, 9.7, and 0.4 for autistic disorder, PDD not otherwise specified, Asperger syndrome, and childhood disintegrative disorder, respectively. During the study period, there was a significant linear increase in prevalence (OR 1.17 per year; 95% CI 1.12 to 1.23). The trend in prevalence of PDDs was unrelated to the discontinuation of TCVs.
Conclusion: Our study provides additional evidence that the PDD rate is close to 1%. We estimate that at least 11 500 Canadian children aged 2 to 5 years suffer from a PDD. The reasons for the upward trend in prevalence could not be determined with our methods. Discontinuation of thimerosal use in vaccines did not modify the risk of PDD.
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http://dx.doi.org/10.1177/070674371005501105 | DOI Listing |
Neurobiol Aging
January 2025
Department of Psychology, The Pennsylvania State University, University Park, PA 16802, United States. Electronic address:
The growing population of older adults emphasizes the need to develop interventions that prevent or delay some of the cognitive decline that accompanies aging. In particular, as memory impairment is the foremost cognitive deficit affecting older adults, it is vital to develop interventions that improve memory function. This study addressed the problem of false memories in aging by training older adults to use details of past events during memory retrieval to distinguish targets from related lures.
View Article and Find Full Text PDFPLoS One
January 2025
Division of Dermatology, Department of Medicine, Temerty Faculty of Medicine, University of Toronto, Toronto, Ontario, Canada.
Onychomycosis is a common, difficult to treat nail disorder. Our objective was to explore disparities in current clinical management practices for onychomycosis in patients from underrepresented groups and with specific comorbidities. We conducted a cross-sectional study using the All of Us (AoU) research program.
View Article and Find Full Text PDFPLoS Med
January 2025
Université Paris Cité, Center of Research in Epidemiology and StatisticS/CRESS/Obstetrical Perinatal and Pediatric Epidemiology Research Team (EPOPé), INSERM, INRAE, Paris, France.
Background: The French guidelines have recommended a restrictive policy of episiotomy since 2005. We aimed to assess variations in the prevalence of both episiotomy and obstetric anal sphincter injury (OASI) from the 2010, 2016, and 2021 National Perinatal Surveys.
Methods And Findings: A total of 29,750 women who had given birth to a live infant by vaginal delivery were included.
J Med Internet Res
January 2025
Department of Healthcare Economics and Quality Management, School of Public Health, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Background: The COVID-19 pandemic, declared in March 2020, profoundly affected global health, societal, and economic frameworks. Vaccination became a crucial tactic in combating the virus. Simultaneously, the pandemic likely underscored the internet's role as a vital resource for seeking health information.
View Article and Find Full Text PDFBiometrics
January 2025
School of Statistics and Management, Shanghai University of Finance and Economics, Shanghai 200433, China.
As a commonly employed method for analyzing time-to-event data involving functional predictors, the functional Cox model assumes a linear relationship between the functional principal component (FPC) scores of the functional predictors and the hazard rates. However, in practical scenarios, such as our study on the survival time of kidney transplant recipients, this assumption often fails to hold. To address this limitation, we introduce a class of high-dimensional partially linear functional Cox models, which accommodates the non-linear effects of functional predictors on the response and allows for diverging numbers of scalar predictors and FPCs as the sample size increases.
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